本文選題：母線故障 + 采樣值差動(dòng)保護(hù)　； 參考：《南京理工大學(xué)》2017年碩士論文

【摘要】：采樣值差動(dòng)保護(hù)因其動(dòng)作速度快,具有很強(qiáng)的抗擾動(dòng)和容錯(cuò)能力,已漸漸發(fā)展為數(shù)字式母線差動(dòng)保護(hù)的主流原理和標(biāo)準(zhǔn)配置。但由于母線區(qū)外故障時(shí)電流互感器發(fā)生飽和,采樣值差動(dòng)保護(hù)還需要與抗CT飽和識(shí)別判據(jù)配合。本文針對(duì)母線差動(dòng)保護(hù)的這個(gè)焦點(diǎn)問題,研究了電流互感器的飽和機(jī)理,分析了其飽和特性;對(duì)目前國(guó)內(nèi)外已有的母線差動(dòng)保護(hù)抗CT飽和方法進(jìn)行了總結(jié),并比較了它們各自的優(yōu)缺點(diǎn)和性能。闡述了采樣值差動(dòng)保護(hù)的基本原理,對(duì)數(shù)據(jù)窗大小的選取,R和S的合理選擇、制動(dòng)系數(shù)的整定進(jìn)行了分析,并對(duì)模糊區(qū)的大小進(jìn)行了討論。在此基礎(chǔ)上提出了一種改進(jìn)的母線采樣值差動(dòng)保護(hù)判據(jù),該判據(jù)包括突變量啟動(dòng)元件、第一CT飽和周波判據(jù)、基于CT線性傳變區(qū)的采樣值差動(dòng)保護(hù)判據(jù)。判據(jù)利用CT飽和時(shí)的波形特征,以制動(dòng)電流的變化率來檢測(cè)CT線性傳變區(qū)的起點(diǎn),并根據(jù)差動(dòng)電流與制動(dòng)電流的比例關(guān)系確定CT線性傳變區(qū)的終點(diǎn)。該判據(jù)與新型制動(dòng)量差動(dòng)判據(jù)相配合,構(gòu)成完整的母線采樣值差動(dòng)保護(hù)。在PSCAD平臺(tái)中建立故障仿真模型,最后通過在MATLAB平臺(tái)中編寫算法仿真試驗(yàn)了在各種故障類型下此差動(dòng)保護(hù)方案的動(dòng)作情況,探究了故障初始相角差、故障轉(zhuǎn)換時(shí)間、頻率偏移、采樣頻率對(duì)此方案的影響,仿真結(jié)果證明了基于CT線性區(qū)的母線差動(dòng)保護(hù)方案能正確區(qū)分區(qū)內(nèi)外故障,在區(qū)內(nèi)故障時(shí)快速動(dòng)作,區(qū)外故障時(shí)可靠不動(dòng)作,發(fā)生區(qū)外轉(zhuǎn)區(qū)內(nèi)的轉(zhuǎn)換性故障時(shí)能迅速可靠動(dòng)作。
[Abstract]:The sampled-value differential protection has become the mainstream principle and standard configuration of digital busbar differential protection because of its high speed and strong anti-disturbance and fault-tolerant ability. However, due to the saturation of the current transformer outside the busbar fault, the sampling value differential protection needs to be matched with the anti-CT saturation identification criterion. Aiming at this focus of busbar differential protection, this paper studies the saturation mechanism of current transformer, analyzes its saturation characteristics, summarizes the existing anti-CT saturation methods of busbar differential protection at home and abroad. Their advantages, disadvantages and performances are compared. The basic principle of sampled-value differential protection is expounded. The reasonable selection of data window size R and S and the setting of braking coefficient are analyzed and the size of fuzzy region is discussed. On this basis, an improved bus sampling value differential protection criterion is proposed. The criterion includes abrupt start element, the first CT saturated Zhou Bo criterion, and the sampling value differential protection criterion based on the CT linear transmission region. The criterion uses the waveform characteristics of CT saturation to detect the starting point of CT linear transmission region by the change rate of braking current, and determines the terminal point of CT linear transmission region according to the ratio of differential current and braking current. This criterion is compatible with the new braking differential criterion and forms a complete busbar sampling value differential protection. The fault simulation model is established in PSCAD platform. Finally, the operation of the differential protection scheme under various fault types is tested by programming algorithm in MATLAB platform, and the initial phase angle difference, fault conversion time and frequency deviation are explored. The effect of sampling frequency on this scheme is proved by the simulation results. The bus differential protection scheme based on CT linear region can correctly distinguish the fault inside and outside the area, and can act quickly in the fault area and reliably not in the fault outside the area. It can act quickly and reliably when the transition fault occurs in the outer turning area.
【學(xué)位授予單位】：南京理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TM773

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 劉益青;高偉聰;王成友;孫天德;高厚磊;;基于差電流半周積分特征的電流互感器飽和識(shí)別方法[J];電網(wǎng)技術(shù);2016年09期

2 李曉華;戴揚(yáng)宇;丁曉兵;楊通，

本文編號(hào)：1818246